You're most likely to encounter pulse oximeters in your doctor's office or a hospital setting, but you can purchase them yourself for use at home. Make sure you consult with a physician on how to properly interpret the readings from your pulse oximeter, or to understand readings taken in a clinical setting.
Definition
A pulse oximeter is a device that measures the amount of oxygen carried in your blood by measuring the differences in light absorbed as the blood moves through your veins.
Readings
Most healthy individuals will have a pulse oximetry reading of between 96 and 99 percent.
Problems
Excessive overhead lighting, movement of the probe, nail varnish or reduced circulation may all cause inaccurate readings from a pulse oximeter.
Warning
A reading of anything less than 90 percent is known as acute respiratory failure. In some cases, those with chronic pulmonary or cardiovascular disorders may fall below this percentage in everyday life.
Function
The human eye often cannot detect signs of insufficient oxygen absorption until the subject's blood is carrying 80 percent or less of the maximum blood possible; a pulse oximeter can sound an alarm at any set saturation level, alerting medical professionals to this condition much faster than the human eye.
Fluctuation
An individual's saturation levels will typically vary in a range of about 3 to 4 percent if there are no other health conditions affecting the readings.
